Question: When did Equatorial Guinea have reserves of 2.90684e+09?
Paraphrase: In what year did Equatorial Guinea have reserves of 2.90684e+09?
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q983 p:P2134 ?s . ?s ps:P2134 ?x filter(contains(?x , '2.90684e+09')) . ?s pq:P585 ?value}